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A139388
Nearest integer to (log(744+(12(n^2-1))^3)/Pi)^2.
2
4, 12, 19, 25, 29, 33, 37, 40, 43, 46, 48, 51, 53, 55, 57, 59, 61, 62, 64, 65, 67, 68, 70, 71, 73, 74, 75, 76, 77, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 90, 91, 92, 93, 94, 95, 95, 96, 97, 98, 98, 99, 100, 101, 101, 102, 103, 103, 104, 105, 105, 106, 106, 107, 108
OFFSET
1,1
COMMENTS
The well-known integers very close to e^(pi sqrt n) for n=A003173(m) are of the form (12(k^2-1))^3+744. This sequence gives the rounded n-value corresponding to a given k.
REFERENCES
See A138852 for links, references and more information.
PROG
(PARI) A139388(n)=round((log(744+(12*(n^2-1))^3)/Pi)^2)
CROSSREFS
Cf. A138851-A138852, A003173, A014708, A056581 and references therein.
Sequence in context: A244433 A086109 A275116 * A300746 A301190 A301184
KEYWORD
nonn,easy
AUTHOR
M. F. Hasler, Apr 17 2008
STATUS
approved